Group-III nitrides are material compounds of nitrogen (N) and the elements in the first column of the p-element block of the periodic table (technically, group IIIB): boron (B), aluminium (Al), gallium (Ga), indium (In) and thallium (Tl). The compounds AlN, GaN, InN and their alloys are technologically important semiconductors with multiple applications in optoelectronics, in particular incorporated in LEDs for light production. Much of my work during my PhD at the Tyndall National Institute focused on the study of some of the properties of these materials.
The use of nitrides as versatile semiconductor materials has driven significant advances over the last two decades in the field of optoelectronic applications. This is mainly due to the fact that the wurtzite (WZ) III-N materials are all direct band gap semiconductors. By alloying GaN (Eg = 3.43 eV), InN (Eg = 0.64 eV) and AlN (Eg = 6.14 eV) one gains potential access to the whole visible spectrum, as well as near infrared (IR) and ultraviolet (UV), as shown in the featured figure in a direct comparison with other III-V materials.
There are a number of challenges related to using III nitrides in semiconductor devices, mostly involving large built-in material strains and piezoelectric fields, which were the focus of my PhD thesis. Read more about our research on group-III nitrides on our Wiki.